Study of the possibility of using pumps in turbine mode.

The article discusses the possibilities of using pumps in turbine mode and presents the results of research in this direction. Calculation and theoretical experimental studies have been carried out on a model of two versions of impellers for turbine and pump modes of operation in the flow part of a reversible hydraulic machine with a speed of 200 rpm and they have the same number of blades, values of b0 and Dvc and blade installation angle βblade on the pressure side, but differ in geometry meridional section and interlobular channel. The dependences of the pressure coefficients, power and efficiency in turbine and pump modes on the flow coefficient were obtained. Results optimization of blade geometry leads to a significant increase in efficiency in turbine and pump modes for impellers and, accordingly, to a decrease in the values of h and q compared to experimental ones. In addition, a comparison of calculated and experimental data is provided for pumps in the speed range nSH=56–297 rpm. And also, the results of deviations of calculated and experimental data, reaching up to 5% in pressure, and up to 12% in flow rate. [ABSTRACT FROM AUTHOR]